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Diffstat (limited to 'src/mem/noncoherent_xbar.hh')
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diff --git a/src/mem/noncoherent_xbar.hh b/src/mem/noncoherent_xbar.hh new file mode 100644 index 000000000..122fc6b27 --- /dev/null +++ b/src/mem/noncoherent_xbar.hh @@ -0,0 +1,211 @@ +/* + * Copyright (c) 2011-2014 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Copyright (c) 2002-2005 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ron Dreslinski + * Ali Saidi + * Andreas Hansson + * William Wang + */ + +/** + * @file + * Declaration of a non-coherent crossbar. + */ + +#ifndef __MEM_NONCOHERENT_XBAR_HH__ +#define __MEM_NONCOHERENT_XBAR_HH__ + +#include "mem/xbar.hh" +#include "params/NoncoherentXBar.hh" + +/** + * A non-coherent crossbar connects a number of non-snooping masters + * and slaves, and routes the request and response packets based on + * the address. The request packets issued by the master connected to + * a non-coherent crossbar could still snoop in caches attached to a + * coherent crossbar, as is the case with the I/O bus and memory bus + * in most system configurations. No snoops will, however, reach any + * master on the non-coherent crossbar itself. + * + * The non-coherent crossbar can be used as a template for modelling + * PCIe, and non-coherent AMBA and OCP buses, and is typically used + * for the I/O buses. + */ +class NoncoherentXBar : public BaseXBar +{ + + protected: + + /** + * Declare the layers of this crossbar, one vector for requests + * and one for responses. + */ + typedef Layer<SlavePort,MasterPort> ReqLayer; + typedef Layer<MasterPort,SlavePort> RespLayer; + std::vector<ReqLayer*> reqLayers; + std::vector<RespLayer*> respLayers; + + /** + * Declaration of the non-coherent crossbar slave port type, one + * will be instantiated for each of the master ports connecting to + * the crossbar. + */ + class NoncoherentXBarSlavePort : public SlavePort + { + private: + + /** A reference to the crossbar to which this port belongs. */ + NoncoherentXBar &xbar; + + public: + + NoncoherentXBarSlavePort(const std::string &_name, + NoncoherentXBar &_xbar, PortID _id) + : SlavePort(_name, &_xbar, _id), xbar(_xbar) + { } + + protected: + + /** + * When receiving a timing request, pass it to the crossbar. + */ + virtual bool recvTimingReq(PacketPtr pkt) + { return xbar.recvTimingReq(pkt, id); } + + /** + * When receiving an atomic request, pass it to the crossbar. + */ + virtual Tick recvAtomic(PacketPtr pkt) + { return xbar.recvAtomic(pkt, id); } + + /** + * When receiving a functional request, pass it to the crossbar. + */ + virtual void recvFunctional(PacketPtr pkt) + { xbar.recvFunctional(pkt, id); } + + /** + * When receiving a retry, pass it to the crossbar. + */ + virtual void recvRetry() + { panic("Crossbar slave ports should never retry.\n"); } + + /** + * Return the union of all adress ranges seen by this crossbar. + */ + virtual AddrRangeList getAddrRanges() const + { return xbar.getAddrRanges(); } + + }; + + /** + * Declaration of the crossbar master port type, one will be + * instantiated for each of the slave ports connecting to the + * crossbar. + */ + class NoncoherentXBarMasterPort : public MasterPort + { + private: + + /** A reference to the crossbar to which this port belongs. */ + NoncoherentXBar &xbar; + + public: + + NoncoherentXBarMasterPort(const std::string &_name, + NoncoherentXBar &_xbar, PortID _id) + : MasterPort(_name, &_xbar, _id), xbar(_xbar) + { } + + protected: + + /** + * When receiving a timing response, pass it to the crossbar. + */ + virtual bool recvTimingResp(PacketPtr pkt) + { return xbar.recvTimingResp(pkt, id); } + + /** When reciving a range change from the peer port (at id), + pass it to the crossbar. */ + virtual void recvRangeChange() + { xbar.recvRangeChange(id); } + + /** When reciving a retry from the peer port (at id), + pass it to the crossbar. */ + virtual void recvRetry() + { xbar.recvRetry(id); } + + }; + + /** Function called by the port when the crossbar is recieving a Timing + request packet.*/ + virtual bool recvTimingReq(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the crossbar is recieving a Timing + response packet.*/ + virtual bool recvTimingResp(PacketPtr pkt, PortID master_port_id); + + /** Timing function called by port when it is once again able to process + * requests. */ + void recvRetry(PortID master_port_id); + + /** Function called by the port when the crossbar is recieving a Atomic + transaction.*/ + Tick recvAtomic(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the crossbar is recieving a Functional + transaction.*/ + void recvFunctional(PacketPtr pkt, PortID slave_port_id); + + public: + + NoncoherentXBar(const NoncoherentXBarParams *p); + + virtual ~NoncoherentXBar(); + + unsigned int drain(DrainManager *dm); + + /** + * stats + */ + virtual void regStats(); + Stats::Scalar totPktSize; +}; + +#endif //__MEM_NONCOHERENT_XBAR_HH__ |